The overall objective is to Develop Apparatus and Procedures to Assess and Optimize positive airway pressure (PAP) treatment of sleep-disordered breathing (SDB) in the Unattended Home Environment by - (a) Daily Measurement and Review of Multiple Physiological Parameters, (b) Assessment of Patient Compliance and Subjective Response, (c) Monitoring the Integrity and Efficacy of the Therapeutic Device, and (d) Facilitating and Expediting any therapeutic adjustment. All these Activities are to be automatically implemented from a remote location using a secure Internet Web Site. The work will utilize a commercially available reflectance Pulse Oximetry Sensor modified to incorporate pressure control and be installed into the forehead support of existing commercially available patient interfaces for nasal positive airway pressure treatment. The oximetry information will be recorded in an Internet-enabled, "Home-Hub" device that will also measure and record nasal airflow, airflow wave form, mask/mouth air leak, snoring, PAP pressure, patient compliance, subjective complaints, quality-of-life measures, and the integrity and performance of the PAP or ventilatory support device. Each day, the data will be automatically accessed and uploaded to a secure, Internet Web Site for immediate automatic review, and (as necessary) further evaluation by qualified clinical specialists and clinical intervention. The patient can also use the Home-Hub to initiate an interaction with the web site. Sleep Disordered Breathing and Obstructive Sleep Apnea (OSA) in particular, is a common, often serious, and sometimes life-threatening disorder that is a major risk factor for cardiovascular disease (including hypertension, cardiac arrhythmias, heart-failure and stroke) and functional impairment during wakefulness (a major cause of industrial and automobile accidents, and work loss). The most effective treatment for OSA prevents the upper airway collapse during sleep by increasing the air pressure by a device called nasal-CPAP; however it is usually important and sometimes essential to be able to monitor the efficacy of this treatment as well as the ability of the patient to comply with the therapy. [unreadable] [unreadable] [unreadable]